1. Field of the Invention
This invention relates to a treating instrument for use with an endoscope, which is introduced through a channel of an endoscope into the body cavity to treat the diseased part.
2. Description of the Prior Art
Among known typical treating instruments for use with an endoscope are one disclosed in U.S. Pat. No. 4,190,942, another disclosed in Japanese Utility Model Disclosure No. 54-63989 and still another disclosed in Japanese Utility Model Publication No. 46-23833. Any of these treating instruments is introduced through the channel of an endoscope into the body cavity. While observing the treated part through an endoscope, the operator can handle the treating instrument to remove and recover foreign objects such as a calculus, for example, or to take samples of living tissue from the body.
A conventional treating instrument is provided at its distal end with a treating element such as a cup part or a holding part. The treating element of a conventional treating instrument has directionality that it can reach foreign objects such as a calculus or the tissue of the diseased part only from a specific direction. The insertion section of an endoscope that has been inserted into the body cavity is bent following the shape of the body cavity. Generally, the bent part at the distal end portion of the insertion section is bent toward the treated part.
When a conventional treating instrument is inserted into the channel of an endoscope which is bent as described above, it is no easy matter to direct the distal end or the treating element of the instrument to a direction suitable for treatment of a calculus, for example, The direction of the distal end of the treating instrument can be changed by rotating the whole body of the endoscope. However, there is a possibility of losing sight of the object in rotating the endoscope. Also, the distal end of the treating instrument can be rotated by rotating the operating section of the instrument. However, when the operating section is rotated, there is a problem that the operating section and the distal end of the treating instrument do not rotate with exactly the same rotating angle due to the friction between the external circumferential surface of the intermediate part and the internal circumferential surface of the channel of the endoscope. When the operating section is rotated while observing the position of the distal end or the treating element of a treating instrument, the whole treating instrument often turns around, reverting to its former position in an instant.
As has been described, when a conventional treating instrument for use with an endoscope is used in the body cavity, it is difficult to set the direction of the distal end of the treating element readily, accurately and quickly during its use. For this reason, a long time has been required for treatment of the patient and a burden on the patient as well as on the doctor has been very great.